Warrior X700

Notable feature: Articulated arm that can lift 150 lb. swaps in for weapons.

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MAARS

Weight: 235 lb.

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Speed: 7 mph

Weapons: M240B medium machine gun

Notable feature: Programmable no-fire zones to prevent fratricide.At a muddy test track in Grand Prairie, Texas, 13 miles west of Dallas, the robot is winning. It has climbed on top of a sedan, its 2.5-ton bulk propped on the crumpled roof. The car never stood a chance.

The MULE (Multifunction Utility/Logistics and Equipment) is roughly the size of a Humvee, but it has a trick worthy of monster truck rallies. Each of its six wheels is mounted on an articulated leg, allowing the robot to clamber up obstacles that other cars would simply bump against.

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Right now, it's slowly extricating itself from the caved-in roof, undulating slightly as it settles into a neutral stance on the asphalt. This prototype's movements are precise, menacing and slow. When the final product rolls onto the battlefield in six years, it will clear obstacles in stride, advancing without hesitation. And, like the robot cars that raced through city streets in last fall's Pentagon-funded DARPA Urban Challenge, the MULE will use sensors and GPS coordinates to pick its way through a battlefield. If a target is detected, the machine will calculate its own firing solutions and wait for a remote human operator to pull the trigger. The age of killer robots is upon us.

But here at defense contractor Lockheed Martin's test track, during a demonstration for Popular Mechanics, this futuristic forerunner of the robot army has a flat tire. "Actually, this is good," says Michael Norman, Lockheed's project manager for the prototype. "You'll be able to see how quick it is to swap in a new tire." He nods toward an engineer holding an Xbox 360 controller and wearing a gigantic, gleaming backpack that contains a processing computer.

The engineer taps a handheld touchscreen. One of the robot's wheeled legs rotates upward, and a two-man crew goes to work. Each leg has its own hub motor to allow for a variety of ­positions. If one leg is blown off by enemy fire or a roadside bomb, the rest are able to soldier on, with the robot automatically adjusting its center of gravity to stay mobile. It's highly functional. But with its engine powered down--it runs on a Mercedes-built engine originally modified for unmanned aerial vehicles (UAVs)--and one leg cocked gamely in the air, the MULE doesn't look so tough right now.

In fact, the MULE isn't ready for battle. Barely a year old, the prototype is a product of the Army's Unmanned Ground Vehicle program, which began in 2001. It has yet to fire a single bullet or missile, or even be fitted with a weapon. Here at the test track it's loaded down with rucksacks and boxes, two squads' worth of equipment. At the moment, the MULE has no external sensors. "We're 80 percent through the initial phase," Norman says, "but we don't have the perception fully tested. It knows heading and speed, but it's blind."

In other words, it's essentially one of the world's biggest radio-control cars. And, eyeing the robot's familiar controller, I realize I might have a shot at driving it. I know my way around a video-game console, but the engineers are noncommittal about my request to drive the MULE.

The goal, of course, is for the MULE to drive itself. Sitting a short distance away is the prototype's future, a full-size mockup of a weaponized variant, its forward-facing machine gun bracketed by missile tubes. The gleaming sphere set on a short mast looks precisely like a robot's eyeball. It will visually track moving targets, allowing operators to zoom in for a closer look before pulling the trigger. According to the Army, this giant prop represents a revolutionary shift in how we will wage wars. This is the face of the robotic infantry.

Unmanned ground vehicles (UGVs) have already flooded the battlefield. There are at least 6000 robots in use by the Army and Marine Corps in Iraq and Afghanistan. For years these small, remote-control vehicles have allowed troops to peek around corners and investigate suspected bombs. And while unmanned aerial vehicles have been loaded with missiles since 2001, the arming of ground robots is relatively uncharted territory.

Last June the Army deployed the first-ever armed UGVs. Three SWORDS (Special Weapons Observation Remote Direct-Action System) robots landed in Iraq, each equipped with an M249 light machine gun. These UGVs are essentially guns on tracks, a variant of the remote-control Talon bots routinely blown up while investigating improvised explosive devices. When the trio was approved for combat duty, the potential for historic robot-versus-human carnage lit up the blogosphere. Never mind the dozens of air-to-ground Hellfire missiles that have already been launched by a squadron of armed Predator drones over the past seven years--this was a robot soldier, packing the same machine gun used by ground troops.

The historic deployment ended with a whimper after the Army announced that the SWORDS would not be given the chance to see combat. According to a statement from Duane Gotvald, deputy project manager of the Robotic Systems Joint Project Office, which oversees robots used by the Army and Marines, "While there has been considerable interest in fielding the system, some technical issues still remain and SWORDS is not currently funded." The robots never fired a shot, but Gotvald pointed out that the Army's 3rd Infantry Division used them for surveillance and "peacekeeping/guard operations."

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The nature of the robots' "technical issues" remains an open question. The Army has not released details, and officials with Foster-Miller, the Massachusetts-based contractor that developed the SWORDS, refused interview requests for this story. But according to Col. Barry Shoop, deputy head of West Point's electrical engineering and computer science department, the reason armed UGVs continue to lag behind UAVs is because of their mission: close-quarters firefights. "The technical challenges are greater," Shoop says. "Think of the kind of image and graphics processing you need to make positive identification, to use lethal force. That's inhibiting."

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Despite the challenges, armed UGV development is on the rise. Foster-Miller is currently working on a successor to the SWORDS, a larger and more versatile robot called the MAARS (Modular Advanced Armed Robotic System). Technicians in the field will be able to replace the system's M240 machine gun (the same kind currently planned for the MULE) with an arm or trade the tracks for wheels. However, the MAARS requires a human operator to move and acquire targets.

IRobot, the maker of thousands of bomb-defusing PackBots, plans to introduce its Warrior X700 this year. The Warrior is larger than the PackBot and has a similar set of articulated tracks that allows it to climb stairs, and a 150-pound carrying capacity. The company is touting the Warrior's ability to fight fires, haul wounded and serve as a weapons platform. But according to Joe Dyer, the president of iRobot Government & Industrial Robots division, a key benefit of an armed UGV isn't what it can dish out, but what it can take: "A robot can shoot second."

The Warrior is able to follow GPS waypoints, can breach ditches and navigate cramped conditions on its own, but it will still rely heavily on human guidance in a fight. Where weapons are involved, Dyer says, "Autonomy's going to come into robots on little cat's feet."

Like their bomb-poking forebears, weaponized bots are disposable, making them particularly useful in urban warfare, with its high potential for collateral damage and sudden, point-blank firefights. "Robots are fearless, so there's an opportunity to better assess the situation," Dyer says. "That means less risk to noncombatants and to friendly forces."

In urban warfare, where troops often lose the high-tech edge, an armed ground robot is the perfect point man. "Send a robotic platform into a room, and it might take some small arms fire," Shoop says. "But it can be repaired fairly easily. A soldier or Marine is not as easily repaired."

The MULE is toying with my emotions. After running through its full range of articulated positions--a hilarious diagnostic dance routine that has it pivoting, rising and tipping its wheels off the road--the robot is now ramming a car. The sedan offers little resistance, sliding across the asphalt. Like proud owners watching their pit bull tear through a chew toy, the small crowd of defense contractors and engineers are chuckling. Next, the MULE climbs onto a 5-ft.-high platform and prepares to cross a 6-ft. gap.

The robot reels back on its hind legs. It inches forward and falls across the space, its front wheels slamming onto the next platform. Although it was moved into position by a human operator, the robot's terrain-clearing performance was automatic, using internal sensors that track wheel position and speed and two onboard Pentium III processors cycling an array of mobility algorithms. Despite being blind, the MULE is already surprisingly autonomous.

The exact details haven't been worked out, but the goal is for a single sergeant to handle multiple robots. But no matter how sophisticated the robot, Lockheed officials point out, it will never fire without a command from a human operator. Having a person decide when to shoot is a recurring theme in discussions about armed robots.

Maj. David Byers, the assistant program manager for the MULE, compares the likelihood of the robot's weapons discharging accidentally to a modern tank inexplicably firing off a round. Using the UGV's sensors, a human will confirm that each target is a hostile before firing. "Armed robots are still foreign to Army culture," he says. "We need to cultivate the understanding that they are quite safe."

The demonstration is winding down, and after a slew of caveats and reassurances, it's my turn to drive. On a grassy slope overlooking the track, an engineer hands me the Xbox 360 controller. I will not, I'm told, get to wear the shiny Rocketeer backpack.

The game controller is surprisingly standard-issue--no external tweaks or mods. When I hit a button, the prototype rumbles forward. I jam the thumbstick to one side, and the robot turns in place, its fresh wheel screeching, painting a perfect circle on the asphalt. I guide the MULE through a small parking lot, around cars, and across a muddy patch to give the tires a little more traction. The robot is responsive, literally leaning into turns and braking with finesse.

My fingers keep hitting the unused buttons, automatically probing for the one that opens fire. In the sci-fi cult classic The Last Starfighter, the teen hero is drafted into a galactic war. The arcade game he spent hours mastering was really an alien simulator, and with a quick costume change, he's reborn as an ace pilot. For 10 minutes, my fantasy is much better: Years of Saturday afternoons and missed classes and so-called sick days spent clicking away at a game console--it wasn't wasted time; it was training. I have become a crack military robot pilot.

Time's up, and I hand back the controller, the prototype still rumbling away, slightly muddier than I found it. We head down the hill, and as I pass an engineer, I mention how easy it is to drive. "Yeah, we based the controls on Project Gotham Racing," he says. It's a joke, but the quip offers a glimpse of what future warfare might look like--robotic, autonomous and just a little bit chilling.

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Robot Versus Sniper

Securing an intersection is a basic combat task that the Pentagon hopes will one day be tackled by unattended robots. In the scenario below, set in 2020, an armed robot has forged ahead of a squad (not shown) to determine if a sniper is stationed at a key corner. As simple as the mission might seem, it's a huge engineering challenge to program the skills needed for the assignment into a robot's brain. Experts say success will require integrated sensors to double for human sensory organs and powerful processing of the data to mimic human training--and instinct. "What is intuition?" asks Jon Bornstein, head of the Army Research Lab's robotics office. "A series of cues that give a high probability of something occurring."

Despite the challenges, armed UGV development is on the rise. Foster-Miller is currently working on a successor to the SWORDS, a larger and more versatile robot called the MAARS (Modular Advanced Armed Robotic System). Technicians in the field will be able to replace the system's M240 machine gun (the same kind currently planned for the MULE) with an arm or trade the tracks for wheels. However, the MAARS requires a human operator to move and acquire targets.

IRobot, the maker of thousands of bomb-defusing PackBots, plans to introduce its Warrior X700 this year. The Warrior is larger than the PackBot and has a similar set of articulated tracks that allows it to climb stairs, and a 150-pound carrying capacity. The company is touting the Warrior's ability to fight fires, haul wounded and serve as a weapons platform. But according to Joe Dyer, the president of iRobot Government & Industrial Robots division, a key benefit of an armed UGV isn't what it can dish out, but what it can take: "A robot can shoot second."

The Warrior is able to follow GPS waypoints, can breach ditches and navigate cramped conditions on its own, but it will still rely heavily on human guidance in a fight. Where weapons are involved, Dyer says, "Autonomy's going to come into robots on little cat's feet."

Like their bomb-poking forebears, weaponized bots are disposable, making them particularly useful in urban warfare, with its high potential for collateral damage and sudden, point-blank firefights. "Robots are fearless, so there's an opportunity to better assess the situation," Dyer says. "That means less risk to noncombatants and to friendly forces."

In urban warfare, where troops often lose the high-tech edge, an armed ground robot is the perfect point man. "Send a robotic platform into a room, and it might take some small arms fire," Shoop says. "But it can be repaired fairly easily. A soldier or Marine is not as easily repaired."

The MULE is toying with my emotions. After running through its full range of articulated positions--a hilarious diagnostic dance routine that has it pivoting, rising and tipping its wheels off the road--the robot is now ramming a car. The sedan offers little resistance, sliding across the asphalt. Like proud owners watching their pit bull tear through a chew toy, the small crowd of defense contractors and engineers are chuckling. Next, the MULE climbs onto a 5-ft.-high platform and prepares to cross a 6-ft. gap.

The robot reels back on its hind legs. It inches forward and falls across the space, its front wheels slamming onto the next platform. Although it was moved into position by a human operator, the robot's terrain-clearing performance was automatic, using internal sensors that track wheel position and speed and two onboard Pentium III processors cycling an array of mobility algorithms. Despite being blind, the MULE is already surprisingly autonomous.

The exact details haven't been worked out, but the goal is for a single sergeant to handle multiple robots. But no matter how sophisticated the robot, Lockheed officials point out, it will never fire without a command from a human operator. Having a person decide when to shoot is a recurring theme in discussions about armed robots.

Maj. David Byers, the assistant program manager for the MULE, compares the likelihood of the robot's weapons discharging accidentally to a modern tank inexplicably firing off a round. Using the UGV's sensors, a human will confirm that each target is a hostile before firing. "Armed robots are still foreign to Army culture," he says. "We need to cultivate the understanding that they are quite safe."

The demonstration is winding down, and after a slew of caveats and reassurances, it's my turn to drive. On a grassy slope overlooking the track, an engineer hands me the Xbox 360 controller. I will not, I'm told, get to wear the shiny Rocketeer backpack.

The game controller is surprisingly standard-issue--no external tweaks or mods. When I hit a button, the prototype rumbles forward. I jam the thumbstick to one side, and the robot turns in place, its fresh wheel screeching, painting a perfect circle on the asphalt. I guide the MULE through a small parking lot, around cars, and across a muddy patch to give the tires a little more traction. The robot is responsive, literally leaning into turns and braking with finesse.

My fingers keep hitting the unused buttons, automatically probing for the one that opens fire. In the sci-fi cult classic The Last Starfighter, the teen hero is drafted into a galactic war. The arcade game he spent hours mastering was really an alien simulator, and with a quick costume change, he's reborn as an ace pilot. For 10 minutes, my fantasy is much better: Years of Saturday afternoons and missed classes and so-called sick days spent clicking away at a game console--it wasn't wasted time; it was training. I have become a crack military robot pilot.

Time's up, and I hand back the controller, the prototype still rumbling away, slightly muddier than I found it. We head down the hill, and as I pass an engineer, I mention how easy it is to drive. "Yeah, we based the controls on Project Gotham Racing," he says. It's a joke, but the quip offers a glimpse of what future warfare might look like--robotic, autonomous and just a little bit chilling.

Robot Versus Sniper

Securing an intersection is a basic combat task that the Pentagon hopes will one day be tackled by unattended robots. In the scenario below, set in 2020, an armed robot has forged ahead of a squad (not shown) to determine if a sniper is stationed at a key corner. As simple as the mission might seem, it's a huge engineering challenge to program the skills needed for the assignment into a robot's brain. Experts say success will require integrated sensors to double for human sensory organs and powerful processing of the data to mimic human training--and instinct. "What is intuition?" asks Jon Bornstein, head of the Army Research Lab's robotics office. "A series of cues that give a high probability of something occurring."